Physics and astrophysics, chemistry and biochemistry, biology, Earth sciences — reference works, databases and open courses for each discipline. Every block links to primary data sources: from property tables to observation datasets.
Physical and chemical values are almost always published with their conditions: temperature, pressure, state of matter, measurement method. Compare data only under matching conditions.
When citing, name the publishing organisation (NIST, IUPAC, NOAA, NASA) and the year of the reference edition — a link to a website without a version is considered incomplete.
Reference tables: density and melting point, physics and chemistry references →